I’d say the strongest arguments for God are:
I also think there are good arguments for believing that God exists, regardless of the truth-value of God’s existence (e.g. that God’s existence is an irresolvable question, and faith makes life happier/more meaningful in some cases, so it might be good to have faith). And some arguments that I find pretty uncompelling of this nature, like Pascal’s wager, might still be compelling for some people.
Maybe there’s some strength to arguments from religious experience, though I personally am pretty uncompelled by them. I find most cosmological and ontological arguments plain silly -- I’d rate them as two of the weakest categories of arguments for God’s existence in the popular/academic discourse. For instance, I’m not even remotely compelled by the kalam cosmological argument.
I’d say the strongest arguments against God are (I can’t quite pick two, so I’m going with three):
- The notion of God is prima facie absurd (or invokes tons of ad hoc assumptions), and naturalism can explain most observable phenomena
- Generally, God tends to be defined as a mind that created the universe/space-time, but minds are a process that -- to our knowledge -- only exist within space-time/seem to require time to even be coherent
- The universe probably doesn’t have an external/original “cause” of existence, insofar as (1) an efficient cause requires time, and it’s unclear whether simultaneous causation is even possible and (2) philosophers and theoretical physicists seem to converge on a B-theory of time, under which the universe probably doesn’t have a meaningful “origin”
And I think there’s reasonably compelling arguments against particular definitions of God. For instance, I think -- though this is pretty extensively debated in academic philosophy -- the problem of suffering makes it unlikely that God is simultaneously all-knowing, all-powerful, and benevolent. But that’s not really evidence against some version of God existing.